“By the year 2050, in a mere 37 years, Britain will be a majority Muslim nation.”Vincent Cooper, June 13 2013

The background

We don’t normally FactCheck other journalists, mainly because there’s enough spin from politicians to keep us busy.

But readers have asked for our take on a piece published on the Commentator website, which has generated a lot of online interest.

Vincent Cooper’s article, which has apparently attracted 2,600 “likes” on Facebook, suggests that birth rates among Muslims are much higher than among “native Europeans”.

The result is that, less than 40 years from now, the sound of church bells will apparently have been largely replaced by the Muslim call to prayer.

The article says it is based on “demographic facts”. What are the facts?

The analysis

There were 1.6 million Muslims in England and Wales in 2001, or 3 per cent of the population, according to the census. By 2011 the Muslim population had grown to 2.7 million people or 4.8 per cent of the population.

So there’s no doubt that the number of people who identify themselves as Muslims has grown rapidly in recent years.

We’ve tried to phrase that carefully, because most measures of population (the census, the Labour Force Survey) rely on people describing themselves as members of certain religious and ethnic groups, and people’s attitudes about how they identify themselves can change.

The Muslim population of Eastern European countries appeared to soar between 1990 and 2000, but the most likely explanation is that the population didn’t really grow – it’s just people felt more comfortable about identifying themselves as Muslim after the collapse of the communist system, in which religious self-expression was discouraged.

Similarly, some commentators have suggested that part of the apparent leap in the number of Muslims in England and Wales can be explained by a reaction to the “war on terror” and a growing willingness for people to claim Muslim identity.

The Muslim Council of Britain has said that the 2001 figure was an underestimate, because Muslims were reluctant to identify themselves as such at the time.

Nevertheless, it seems likely there has been a real increase in the Muslim population of Britain, due to a mixture of immigration and higher birth rates.

Mr Cooper concentrates on the issue of birth rates, and basically suggests that if fertility among Muslim women continues to be higher than other demographic groups, then extending current trends into the future will give us a Muslim majority by 2050.

That flies in the face of evidence which shows that, while fertility rates have historically been significantly higher among Muslims, birth rates are now dropping among Muslim immigrant populations in Europe and in Muslim countries.

Birth rates levelling off

A 2007 study by demographers Charles Westhoff and Tomas Frejka identified the same trend among Muslim immigrant populations in most countries where data was available, including Austria, Slovenia, the Netherlands, Belgium, Germany, Switzerland and England and Wales.

The total fertility rate among Muslim women is almost always higher than that of the native population, but “with the passage of time Muslim fertility moves closer to the fertility of the majority of the population in the respective countries”.

In this country, the study tracks changing fertility rates among women from Pakistan and Bangladesh (assumed to be overwhelmingly Muslim).

Women from Pakistan and Bangladesh tend to have more children, but the fertility gap shrinks over the decades.

The US Pew Forum think-tank predicts that this gap will continue to diminish in the coming decades in all European countries.

It put the 2005-10 fertility rate among UK Muslims at 3.0, which means that the average British Muslim had exactly three children in her lifetime, compared to 1.8 children for non-Muslim women.

By 2030 the rate is predicted to fall to 2.5 for Muslims and remain at 1.8 for non-Muslims.

Clearly this does suggest that there will be an increase in the size of the Muslim population, but the prediction comes a long way short of the numbers claimed by Mr Cooper.

Assuming patterns of net immigration do not change significantly, the Pew Forum thinks that there will be just over 5.5 million British Muslims, representing 8.2 per cent of the UK population, by 2030.

None of this is an exact science, and some demographers say total fertility rate overestimates the lifetime fertility of immigrants because it doesn’t adjust for the fact that they tend to have children soon after arriving.

The verdict

Birth rates among native-born women are currently low across most of Europe and the developed world in general.

Demographers think a fertility rate of about 2.1 children per woman on average is necessary for the population of a developed country to sustain itself.

Most of the “native” populations of Europe are failing to have enough children, while birth rates are higher among Muslim immigrant populations, so it seems inevitable that the British Muslim population will rise in the coming decades.

But it’s equally clear that the gap in fertility between Muslim and non-Muslim will continue to lessen over time, as it has in recent decades.